Sliding clasp fastener



Filed June 5, 1966 United States Patent 5 Claims. of. 24-2051 ABSTRACT OF THE DISCLOSURE A sliding clasp fastener in which substantially U-shaped connecting elements provided on the basis thereof with coupling faces are connected by sewing two stringers which are folded along a longitudinal fold line so as to cover the respective connecting elements and to form two layers from the stringer against one of which one limb of each U-shaped conecting element abuts and in which the sewing comprises a stitch for each connecting element which stitch is adjacent a coupling face of the respective connecting element and engages only said one layer and said one limb which abuts against said one layer.

The invention relates to a sliding clasp fastener in which the clasps or connecting elements are made separate from the stringers and have superposed mounting limbs adjoining their coupling faces, by means of which limbs the conecting elements are sewn to their stringers. The mounting limbs are superposed in a direction transversely to 'the plane of the stringers and each stringer has a fold which extends up to the line of engagement of the coupling faces for the purpose of covering the connecting elements. The fold is preferably open.

Sliding clasp fasteners of this kind are intended to be concealed by virtue of the above-mentioned fold in each stringer. If it is an open fold, not even the sewing is visible because in that case the stitches for mounting the connecting elements only pass through that part of the stringer which is concealed by the folded over or turned back portion of the stringer.

Known such fasteners, however, have the disadvantage that the folds do not always cover the rows of connecting elements. If a pull is exterted on the stringers in a direction transversely to the interengaging connecting elements, and such a pull occurs frequently when wearing garments fitted with such sliding clasp fasteners, then the marginal folds in the stringer are displaced in the direction of such pull. The connecting elements then become visible between the gaping marginal folds.

The invention aims to provide a sliding clasp fastener in which the folds in the stringers provide good coverage for the connecting elements even if a pull is exerted on the stringers transversely to the connecting elements.

It has been found that undesirable gaping of the folds in the stringers as a result of lateral pulling is caused by the fact that the stitches mounting the connecting elements undergo expansion and, as viewed in cross-section of the rows of connecting elements, the end of the stitches engaging the stringer are displaced into an oblique position. To solve this problem it is necessary that the stitches are prevented from such displacement so that the spacing between the fold lines in the stringer cannot become excessive.

Acocrding to the invention, the sewing attaching the clasps or connecting elements to the stringers comprises a stitch for each connecting element, which stitch is immediately adjacent a coupling face and engages only that of the superposed limbs which lies against the respective stringer. This stitch, which is closely behind a coupling "ice face and which would first be subjected to any pull that may be exerted on the stringers and which is responsible for undesirable gaping of the stringers, will thus be comparatively short because it engages only one of the mounting limbs. Consequently, any pull will cause only very little expansion of the short stitch and there will be hard- .ly any displacement of the stitch on the connecting element. Gaping of the folds which cover the coupling faces will therefore be practically impossible.

There may be additional stitches for securing the clasps or connecting elements to the stringers. To assist in preventing displacement, these additional stitches may be located closely behind the stitch that is directly adjacent the coupling face and in this way the additional stitches will constitute an abutment for the first-mentioned stitch. Another way of enhancing the security against displacement of the first stitch would be the provision of formations at those parts of the mounting limbs which come into contact with the stitches. These formations may be in the form of notches or projections which serve as a fixed abutment for the stitches.

The aforementioned additional stitches can either engage only the one mounting limb in the same way as the first stitch or they may engage both of the superposed mounting limbs. The second alternative is of particular significance in the case where the connecting elements are in the form of a spacial or three dimensional meander whose two limbs are spaced apart at the side remote from the coupling faces. The additional stitches engaging both limbs have the effect of holding the two limbs together, together with an insert which may be located between the two limbs and ensure a desired spacing between the two limbs.

The proposed construction with connecting elements in the form of a spacial meander is very readily obtainable. The row of connecting elements is firstly applied to a marginal strip of a flat stringer whilst the two limbs of each element are splayed apart and those limbs which face the edge of the stringer are sewn to the latter in the vicinity of the coupling faces. Thereafter the limbs remote from the edge of the stringer are bent over about the coupling faces to overlie the limbs which are already attached to the stringer and in this position they are fastened by additional stitches which engage both limbs. Finally, the free portion of the stringer is turned over to form the desired fold in the region of the coupling faces of the connecting elements.

Examples of the invention are illustrated in the accompanying drawings wherein:

FIG. 1 is a fragmentary cross-section through half a sliding clasp fastener and FIGS. 2 to 5 diagrammatically illustrate the individual stages in making a slightly modified sliding clasp fastener.

FIG. 1 shows a half section 10 of a sliding clasp fastener, comprising a row 11 of clasps or connecting elements and a stringer 12 which is provided with a fold 13 in a marginal portion adjacent the row 11 of clasps. The fold 13 covers the clasps and therefore conceals them at the side which would normally be viewed. The apex or line 14 of the fold 13 extends up to the line of engagement of the coupling faces 15 of the row of clasps. At the other side of the coupling faces 15, the fold 13 is open. Of the two layers 16, 17 formed by the fold in the stringer, the wider layer 16 serves to attach the finished fastener to an article such as a garment whilst the narrower layer 17 serves to mount the row of clasps.

The individual clasps 18 in the row 11 are formed by the windings in a plastics wire which is in the form of a three dimensional meander. Each clasp 18 has two mounting limbs 19, 20 which adjoin the coupling faces 15 and are superposed transversely to the plane of the stringer 12 The limb 19 lies directly against the narrower layer 17-of the stringer 12 whilst the other limb 20 is remote therefrom. An insert 21 comprising a bundle of threads is located between the limbs 19, 20 and serves to ensure the desirable spacing between the two limbs. Four stitches 22, 23, 24, 25 serve to secure the clasps 18 to the stringer 12. The first stitch 22 in the vicinity of the coupling faces 15 only engages the. limb 19 which lies directly against the stringer. The next stitch 23 again passes only over the limb 19. At the side of the clasps 18 remote from the coupling faces 15 the other two stitches 24,25 engage the limbs 20 as well as the limbs 19. In addition, the stitches 24, 25 retain the insert 21 between the two limbs.

FIGS. 2 to illustrate the individual stages in the production of a modified sliding clasp fastener. Inasfar as the integers inFIGS. 2 to 5 are the same as those of FIG. 1, the same reference numerals are used but provided with an index stroke.

As shown in FIG. 2, a row 11 of clasps formed from a plastics wire which is initially in the form of a planar meander is laid on a marginal strip 26 of a flat stringer 12. The. limbs 19' directed towards the edge 27 of the stringer are then secured to the stringer 12' by a row of stitches 22 which are immediately adjacent the coupling faces of the clasps 18'. The parts of the limbs 19' coming into contact with the stitches 22 are provided with notches28 in which the stitches 22' are received. FIG. 3 is a cross-section through the stringer taken along the line III-III in FIG. 2.

It is not absolutely essential that the limbs 19, be oppositely directed so that the clasps 18' lie in one plane. All that is necessary is that the limbs 20 leave sufficient room for the stitches 22' to be applied. This could be achieved conveniently if, for example, the limbs 19', 20' are at right angles to one another.

In the next stage of manufacture as shown in FIG. 4, the limbs 20' remote from the edge 27 of the stringer are bent in the region of the coupling faces 15 to lie above the limbs 19'. In this position the two limbs are secured to the stringer 12' by an additional stitch which also serves to secure an insert 21' between the limbs. The stitch 25' engages both the limbs. As shown in FIG. 5, it is now only necessary to fold over the free margin of the stringer 12" to produce the fold 13' which covers the coupling faces 15 of the clasps 18'.

Other forms of construction are possible. For example, instead of separate inserts, the spacing between the two mounting limbs of the U-shaped clasps can be achieved by means of plastics extensions formed on the clasps themselves. One way of doing this would be by providing a hump that is bent into one of the limbs and contacts the other limb. The two limbs could be welded together at such place of Contact. In that case, any additional stitch for engaging both the limbs can be dispensed with. The two limbs could even be directly superposed without a spacing therebetween.

Further, it is conceivable to use rows of clasps formed from a helically wound plastics wire, the clasps again being sewn to the stringer in the vicinity of their coupling faces by means of short stitches.

I claim:

1. A sliding clasp fastener comprising, in combination, stringers; substantially U-shaped connecting elements connected by sewing to respective stringers and having each a pair of superimposed limbs and a base connecting the limbs; coupling faces on the base of each U-shaped connecting element effective to permit releasable interengagement of the connecting elements of one stringer with those on the other stringer; and -a fold in each stringer effective to cover the respective connecting elements and forming two layers in each stringer, one limb of each connecting element abutting against one of said layers, and said sewing comprising a stitch for each connecting element which stitch is adjacent a coupling face of the respective connecting element and engages only said one layer and that one of said superimposed limbs which abuts against said one layer.

2. A sliding clasp fastener according to claim 1, Wherein the connecting elements for each stringer are formed from a wire which meanders in three dimensions.

3. A sliding clasp fastener according to claim 1 wherein the part of each limb contacting the said stitch is provided with a formation serving as an abutment for, the stitch.

4. A sliding clasp fastener according to claim 3 wherein the formation is a notch.

5. A sliding clasp fastener according to claim 1 wherein the said sewing comprises a further stitch for each connecting element whichv further stitch engages both of the superposed limbs.

References Cited UNITED STATES PATENTS 2,067,734 1/1937 Silberman 24-2051 2,067,735 1/ 1937 Silberman 24-205.1 3,143,778 8/1964 Abraham 24-205.l 3,149,387 9/1964 Ruhrrnann.

FOREIGN PATENTS 938,704 10/ 1963 Great Britain. 575,938 4/1958 Italy.

BERNARD A. GELAK, Primary Examiner. 

1. A SLIDING CLASP FASTENER COMPRISING, IN COMBINATION, STRINGERS; SUBSTANTIALLY U-SHAPED CONNECTING ELEMENTS CONNECTED BY SEWING TO RESPECTIVE STRINGERS AND HAVING EACH A PAIR OF SUPERIMPOSED LIMBS AND A BASE CONNECTING THE NECTING ELEMENT EFFECTIVE TO PERMIT RELEASABLE INTERENGAGEMENT OF THE CONNECTING ELEMENTS OF ONE STRINGER WITH THOSE ON THE OTHER STRINGER; AND A FOLD IN EACH STRINGER EFFECTIVELY TO COVER THE RESPECTIVE CONNECTING ELEMENTS AND FORMING TWO LAYERS IN EACH STRINGER, ONE LIMB OF EACH CONNECTING ELEMENT ABUTTING AGAINST ONE OF SAID LAYERS, AND SAID SEWING COMPRISING A STITCH FOR EACH CONNECTING ELEMENT WHICH STITCH IS ADJACENT A COUPLING FACE OF THE RESPECTIVE CONNECTING ELEMENT AND ENGAGES ONLY SAID ONE LAYER AND THAT ONE OF SAID SUPERIMPOSED LIMBS WHICH ABUTS AGAINST SAID ONE LAYER. 